4-Chloropyridine-2-carboxylic acid tert-butyl ester Chemical Properties

Boiling point:

295.3±20.0 °C(Predicted)

Density 

1.173±0.06 g/cm3(Predicted)

storage temp. 

under inert gas (nitrogen or Argon) at 2-8°C

pka

-0.10±0.10(Predicted)

Appearance

White to off-white Solid

CAS DataBase Reference

220000-86-2

4-Chloropyridine-2-carboxylic acid tert-butyl ester Usage And Synthesis

Uses

tert-Butyl 4-Chloropicolinate is used in the synthetic preparation of 2-aminobenzimidazoles as Raf kinase inhibitors.

Synthesis

At -40 °C, 4-chloropyridin-2-yl chloride (9.0 g, 51.1 mmol) was dissolved in 1,2-dichloroethane (60 mL) and added slowly and dropwise to a mixed solution containing tert-butanol (25 mL), pyridine (20 mL) and 1,2-dichloroethane (80 mL). The reaction mixture was heated at 50°C for 24 hours. After completion of the reaction, the reaction mixture was diluted with dichloromethane and washed sequentially with 5% aqueous citric acid solution and saturated aqueous NaHCO3 solution. The organic layer was dried with anhydrous MgSO4, filtered and concentrated. Purification by fast column chromatography (silica gel as stationary phase, 20% ethyl acetate/dichloromethane as eluent) afforded tert-butyl 4-chloropyridine-2-carboxylate (9.8 g, 90% yield) as a clarified oil. m/z 213 (M+), 158 (M-Bu+) by LC-MS.

References

[1] Patent: US2005/239820, 2005, A1. Location in patent: Page/Page column 17
[2] Patent: US2013/35492, 2013, A1. Location in patent: Paragraph 0173
[3] Patent: WO2010/51373, 2010, A1. Location in patent: Page/Page column 65
[4] Patent: WO2012/112570, 2012, A1. Location in patent: Page/Page column 49
[5] Patent: US2013/60043, 2013, A1. Location in patent: Paragraph 0176; 1077; 0178

4-Chloropyridine-2-carboxylic acid tert-butyl ester(220000-86-2)Related Product Information

• 4-Chloropyridine-2-carboxylic acid tert-butyl ester
• Di-tert.-butyl 4-chloro-2,6-pyridinedicarboxylate
• 4-Chloropyridine-2-carboxylic acid ethyl ester